Chicago Zoo's vaccination program is leading the way in fight to eradicate disease from Africa

Sunday

Dec 30, 2012 at 12:01 AM

NANGALE, Tanzania — Huddled with his younger brother, the young man laughs easily, conspiratorially, at the commotion caused by the presence of curious foreigners in his family's modest compound outside this small village.

STEVE JOHNSON

NANGALE, Tanzania — Huddled with his younger brother, the young man laughs easily, conspiratorially, at the commotion caused by the presence of curious foreigners in his family's modest compound outside this small village.

But when you ask 19-year-old Maduhu Ginyebu about the scars that tightened and twisted his face, his mood darkens and he sighs heavily. He talks about "other boys laughing" at him.

His father, in a woolen sport coat he has put on to greet the visitors on this 90-degree October day, says his family has been taunted in the village as "hyena leftovers."

The Ginyebus know wild animals. They live six miles from the world-renowned Serengeti National Park, where tourists pay thousands of dollars to photograph the same wildlife the family sees as part of ordinary life: leopards, wildebeest, jackals and, most often, hyenas.

But the animal that visited them in September 2000 was different, its body coursing with a disease that had maddened and would soon kill it. The rabid hyena, 100-plus pounds of slavering predator, burst into the family's sleeping quarters and tore at Maduhu and whatever other flesh it could find — his father's wrist, his brother's chest, his mother's hand — before being beaten away and running off to inflict a similar hell upon a neighboring family, disfiguring several young girls.

"We had fences. We had dogs," the girls' mother, Magaja Misozi, said. "When it comes to the rabid hyena, there is nothing you can do."

The fight to end such attacks traces to an unexpected place: Chicago's Lincoln Park Zoo, a 35-acre lakefront attraction half a world away, in a country where rabies is all but invisible. The zoo heads a decade-long effort to keep rabies from spreading into wildlife by vaccinating dogs against the virus in villages that border the Serengeti park.

Last spring the project delivered its 1 millionth vaccination, a standard concoction that also protects against canine distemper and parvovirus. If that milestone shot was administered in the project's usual manner, it was done with almost the opposite of fanfare: a dog squeezed between its owner's legs, a needle pulled from a battered cooler, a quick skin prick and a plunge.

The results have been far less prosaic. Lions and African wild dogs, already endangered predators, were dying in the Serengeti of canine distemper and rabies. With the infectious diseases all but wiped out in the dogs that were the diseases' main carriers, the lion population is back to pre-epidemic levels and African wild dogs have recently been reintroduced to the park.

More powerful has been the effect on people: The program, known as the Serengeti Health Initiative, has virtually eliminated rabies transmission from dogs to humans in the villages within the 6.2-mile-wide vaccination zone around the Serengeti. Hard statistics don't exist, but scientists estimate that the program has saved up to 150 lives annually, many of them children who are the caretakers of domestic dogs.

"You learn about this vaccination program, and the goal of it was to prevent these (disease) outbreaks in Serengeti National Park and to conserve the wildlife and the ecosystem there," says Anna Czupryna, a doctoral candidate from Chicago studying the effects of the vaccination program. "But along with that we've eliminated rabies in villages such as Nangale."

She recalls meeting the Misozi girls earlier in the day. Twelve years after the attacks, one girl still can't chew properly; one, ashamed of how she looks, rarely leaves the house. "That we can actually prevent that from happening to other people is amazing," Czupryna says.

The program — and others like it — has helped spur new global action against rabies. The most optimistic scientists believe they can essentially eradicate the disease worldwide after years of living with a toll conservatively estimated at 70,000 deaths a year, almost all in Asia and Africa.

Other zoonotics — diseases that transfer from animals to humans — get more publicity: SARS, swine flu, avian flu. But rabies is many times more lethal and almost wholly preventable. To many, that is an unconscionable combination.

"It's just wrong, it's basically wrong, that a child living in a village bitten by a rabid dog is going to die a horrible death because he can't afford to go to a hospital," says Sarah Cleaveland, who was a lead scientist in the Serengeti initiative and remains, from her post at the University of Glasgow in Scotland, a leader in global anti-rabies efforts. "It's a disease that we just simply shouldn't have to be living with in the 21st century."

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Animals are central to life in this arid, grassy region of east Africa.

At the Ginyebus, chickens strut through the center of the yard, meals almost ready to eat. Eleven head of cattle, the family's wealth, mill about in a pen attached to the tree-limb fence that defines the family's domestic enclosure, or "kaya," in the local Sukuma language.

In a dark, protected cranny of the grain storage hut, a dog nurses the pups she gave birth to the night before.

The Ginyebus' is "Nhh076," or "Nangale Village household No. 76," in the ongoing research project chronicling the Serengeti Health Initiative's impact. The visitors this day include Czupryna, 31, a Northwest Sider who lives in Tanzania from August to December each year to lead the research; Chunde Bigambo, the Tanzanian who is Lincoln Park Zoo's jack-of-all-trades — equal parts scientist, driver, ambassador and translator; and Lisa Faust, the zoo's recently appointed vice president for conservation and science and one of Czupryna's doctoral advisers, who is touring the Tanzanian effort for the first time as an administrator.

Czupryna, an effusive, compulsively organized, first-generation Polish-American, focuses on the household dogs. She is especially interested in the new births, because she is trying to learn what happens to the size and health of an area's dog population after it starts receiving rabies vaccinations.

"I've got at least four puppies, possibly a fifth," she announces, emerging from the protected birthplace.

Domestic dogs are the key because they are the primary hosts and transmitters of rabies. The virus spreads into wild animals when there is contact with infected dogs — as they tangle alongside grazing cattle, for instance. But research has shown that vaccinating 70 percent of a region's domestic dogs will prevent them from becoming a host population.

Czupryna gathers as much data as possible, recording it in field notebooks, in photographs and on a small laptop. She weighs the dogs when she can, photographs their teeth, takes fecal samples she'll transport to Chicago for analysis.

"It gets a little OCD at times," says Faust, an expert in population genetics and a former field researcher herself, "but then you have this rich data set to go back to."

Part of that data set involves the Ginyebus' firsthand experience with rabies.

"Six people were bitten by hyena in year 2000," says the questionnaire the family fills out, with help from Bigambo, in the section labeled "Table N: Human Bite Incidence."

Below that, the form asks: "Do you know what rabies is?" The response: "Disease that caused animal to go mad (crazy and starts to bite people)."

"We (have been) participating in the study because of the attack," says the father, 69-year-old Buyombo Ginyebu.

Telling of that night, the family members speak, in Sukuma, without dramatic flourish. "We just accept what we have," Buyombo Ginyebu says. "We blame the rabies and the hyena, too."

Hyenas look like some sort of genetic misfire, animals whose component parts seem just on the brink of fitting together, but they are forceful enough to drive a cheetah from its downed prey in the Serengeti grasslands. Imagine that power stoked by madness and unleashed in darkness, within a rural family's close, mud-brick walls.

Maduhu's mother holds up her left hand to display the place where a thumb was once attached. His father pushes back his long sleeves to show wrists badly damaged from fending off the carnivore. Maduhu, just 7 when he was bitten on the nose and cheek, doesn't have to make any special effort to show what happened to him, nor can he hide it.

After the attack, the wounded family members were taken to a medical clinic in the much bigger town of Bariadi, 37 miles away. The family sold its greatest asset, seven cattle, to pay for months of further treatment; the herd has been rebuilt through the kindness of relatives, the Ginyebus say.

Early the next morning, villagers tracked and killed the hyena, beating the rabies virus to the punch.

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In the developed world, it is easy to think almost nothing about rabies. We know the legends, of course. Viciousness. Depravity. A disease that, unless treated before symptoms appear, is nearly 100 percent fatal and horrific in its final throes.

In their 2012 cultural history "Rabid," Bill Wasik and Monica Murphy describe the disease's tortures. A common one: Almost all rabid humans develop a passionate thirst and an equally passionate revulsion to water. Rabies, they note, may have inspired the werewolf, vampire and zombie legends.

"Rabies is a scourge as old as human civilization, and the terror of its manifestation is a fundamental human fear, because it challenges the boundary of humanity itself," writes Wasik, a science writer, and his wife, Murphy, a veterinarian. "For the rabid bite is the visible symbol of the animal infecting the human, of an illness in a creature metamorphosing demonstrably into that same illness in a person."

We also know that Louis Pasteur took care of all that. In 1885, the French scientist and his team developed the first working vaccine by spreading rabies to rabbits, then drying their infected nerve tissue and mixing it into a potion. A 9-year-old boy bitten by a rabid dog was the first human recipient, and Pasteur's gamble worked. Instead of contracting rabies, the boy produced antibodies that fought off the virus before it spread through his nervous system into the brain.

Now — in most of the developed world, at least — domestic dogs, once rabies' greatest transmitters, get annual vaccine shots, and incidence of the disease is reduced to the occasional bite from an infected bat, fox or raccoon. In the U.S., human deaths related to rabies have declined to one or two a year, according to the Centers for Disease Control and Prevention.

Through science and custom, rabies has been reduced to a relic of a darker past.

But in the developing world, in parts of Africa and Asia, science wasn't sure that domestic dogs were the transmitters. It wasn't sure how many dogs were, in fact, domestic: To Western eyes, all of the dogs — sleeping outside, foraging for food — looked a little wild.

"There was so much in the literature saying there's no point trying to control rabies in Africa," says Cleaveland, the Glasgow epidemiologist. "All of these reasons were really sort of barriers to doing anything about rabies."

And because people lacked cash and education, and rabies treatment was expensive and often distant, thousands of people were dying each year of bites from rabid animals.

That was the state of things when Cleaveland began working in Tanzania in the 1990s. Not only were people dying, but canine distemper was ravaging the Serengeti's lion population, eventually killing a third of the estimated 3,000 lions living there. The rabies virus was even more lethal to the park's African wild dogs: A much smaller population disappeared, going off to die, it was theorized, in underground dens.

After an effective trial project, Cleaveland and her colleagues won National Science Foundation grants to, in part, test the Western model of rabies prevention, beginning in 2003. They would inoculate the dogs in villages bordering the park, testing their theory that the viruses were entering park animals through contact with domestic dogs.

Known then as the Carnivore Disease Project, it was able to prove two things quickly.

There were few stray dogs in Tanzania, meaning that previous assumptions were wrong, and, if owners bought into the project, dogs could be vaccinated in rates sufficient to be effective.

Vaccinating the dogs was seemingly wiping out the incidence of rabies, not only in park animals but also in people. In lions, meanwhile, the canine distemper epidemic faded to sporadic cases.

"By year three, this was, like, 'Wow,' " says Dominic Travis, the Lincoln Park Zoo's former conservation vice president, who helped persuade the zoo to take over the program after year five. "There was surveillance all over the place, people taking blood, doing autopsies on animals and looking for (rabies) really hard — and starting to not find it really quickly. By year six or seven there hadn't been a case found in a few years."

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